Tight bounds for shared memory systems accessed by Byzantine processes

Summary. We provide efficient constructions and tight bounds for shared memory systems accessed by n processes, up to t of which may exhibit Byzantine failures, in a model previously explored by Malkhi et al. [MMRT03]. We show that sticky bits are universal in the Byzantine failure model for n ≥ 3t + 1, an improvement over the previous result requiring n ≥ (2t + 1)(t + 1). Our result follows from a new strong consensus construction that uses sticky bits and tolerates t Byzantine failures among n processes for any n ≥ 3t + 1, the best possible bound on n for strong consensus. We also present tight bounds on the efficiency of implementations of strong consensus objects from sticky bits and similar primitive objects.

Non-Interventional Weight Changes Are Associated with Alterations in Lipid Profiles and in the Triglyceride-to-HDL Cholesterol Ratio

Background: Obesity is associated with dyslipidemia, and weight loss can improve obese patients’ lipid profile. Here, we assessed whether non-interventional weight changes are associated with alterations in lipid profile, particularly the triglyceride (TG)-to-high-density lipoprotein cholesterol (HDL-C) ratio (TG/HDL-C). Methods: In this retrospective analysis of subjects referred to medical screening, body mass index (BMI), low-density lipoprotein cholesterol (LDL-C), TG, and HDL-C levels were measured annually. Patients were divided according to BMI changes between visits. The primary outcomes were the changes in LDL-C, TG, HDL-C, and the TG/HDL-C ratio between visits. Results: The final analysis included 18,828 subjects. During the year of follow-up, 9.3% of the study population lost more than 5% of their weight and 9.2% gained more than 5% of their weight. The effect of weight changes on TG and on the TG/HDL-C ratio was remarkable. Patients with greater BMI increases showed greater increases in their TG/HDL-C ratio, and conversely, a decreased BMI level had lower TG/HDL-C ratios. This is true even for moderate changes of more than 2.5% in BMI. Conclusions: Non-interventional weight changes, even modest ones, are associated with significant alterations in the lipid profile. Understanding that modest, non-interventional weight changes are associated with alterations in the TG/HDL-C ratio may aid in better risk stratification and primary prevention of CV morbidity and mortality